US Silver

US Silver

US Silver Corporation (Tsxv|USA) is a mining company based in Wallace, Idaho near Coeur d'Alene, Idaho. The Chairman of the Company is John P. Ryan, the CEO is Bruce Reid, and the President is Mark Hartmann.

In 2006 USSC purchased the Coeur, Caladay, and Galena mines from Coeur d' Alene Mines Corporation “Coeur” (NYSE:CDE.) The USSC property covers 10,931 acres over an area about 11 miles long east to west and 3 miles wide. The property contains two mines and one exploration shaft. The operating Galena mine is located near the center of the property position, the Coeur mine which is on care and maintenance is about 1.5 miles west of the Galena mine and the Caladay exploration shaft approximately 2 miles east of the Galena.

History of the District

The Coeur d’Alene Mining District is one of the pre-eminent silver, lead and zinc producing areas in the world, located near the base of the panhandle of northern Idaho, and has produced over 1 billion ounces of silver. Spokane, Washington is approximately 75 miles to the west and Missoula, Montana is approximately 110 miles to the east and extends for over 20 miles in a northwest-southeast direction.

Galena Mine

The Galena mine has a long history dating back to 1887 but the modern history and mining commenced by ASARCO in 1953 in an effort to explore and exploit outcrops of silver-lead ore. At that time a shaft was sunk to the 3000 level (3000 feet below the shaft collar) and lateral or level drifts were excavated on the 2800 and 3000 levels. The level drifts accessed down dip projections of the silver-lead ore from above. The development on these levels included, drifting on ore and excavation of raises between the 2800 and 3000 levels and some diamond drilling. The “lead ore” was ready for production in 1953 when a drift crew on the east end of the 3000 level exposed a wide siderite-tetrahedrite-chalcopyrite vein that assayed over 50 ounces per ton silver. ASARCO abandoned the silver-lead development and focused on this new high grade discovery. The new discovery was called the Silver vein and has been the largest vein found at the Galena to date with estimated production of over 100 million ounces of silver at averages grades of over 20 ounces per ton. From 1953 until present, all exploration, development and production has been focused on the tetrahedrite silver-copper ores.

Because ASARCO focused its efforts in 1953 on the silver-copper veins no systematic exploration program was ever conducted at the Galena for silver-lead ore until USSC took over in 2006. Total production since 1953 is over 160 million ounces of silver, 116 million pounds of copper and 22.0 million pounds of lead from 7.0 million tons of ore. Average grade of the silver-copper ore has been 22.89 ounces per ton of silver and 0.83% copper. Average grade of the silver-lead ore has been 8.18 ounces silver and 8.8% lead per ton of ore. The mine is currently producing silver-copper ore at a rate of approximately 625 tons per day. Ore grades are approximately 24.0 ounces per ton silver and 0.76% copper.

The present day Galena Mine is an underground silver-copper mine and is served by two vertical shafts. The No. 3 shaft is the primary production shaft and is 5,800 feet deep. The Galena shaft primarily provides utility access for water, electrical power and sand backfill for underground operations down to the 4,900 level. The Galena mine also has an operating 1,100 ton per day floatation mill, maintenance shop, carpenters shop office and dry facilities. The mine utilizes conventional and mechanized cut and fill mining methods with sand backfill to extract ore from the high grade silver-copper vein deposits that constitute the majority of the ore reserves. Silver and copper are recovered by a flotation mill that produces a silver rich concentrate which is sold to third-party smelters in Canada. Waste material from the milling process is deposited in a tailings pond located approximately two miles from the minesite. The tailings containment pond, which is expanded on an as needed basis, has capacity for approximately eight additional years at current production rates.

Coeur Mine

The Coeur Mine is an underground silver mine located adjacent to the Galena Mine. The Coeur Mine operated until mid-1998 when the property was placed on care and maintenance. There has been no mining activity at the Coeur mine since that time. The Coeur Mine is connected to the Galena Mine, which allows future discoveries at either mine to be developed and processed at either facility. This connection is currently being utilized to provide ventilation and secondary access to the Galena Mine. The Coeur mine produced continuously from 1969 through 1991 and again from 1996 through 1997. The total production was 39 million ounces of silver and 33 million pounds of copper from 2.4 million tons of ore. Average ore grades were 16.0 ounces per ton silver and 0.68% copper.

This mine is serviced by an operational three compartment shaft with a double drum hoist that goes to 4,000 feet below the surface. The Coeur mine also has a 600 ton per day flotation mill, maintenance shop, office and dry facility. The Coeur Mill was put back into production in October, 2007 to process lead-silver ores from the Galena Mine. The concentrates produced are shipped to Trail, BC and processed by Teck-Cominco.

Caladay Property

The Caladay property adjoins the Galena Mine. Prior to its acquisition by Coeur in 1991, approximately $32.5 million was expended on the property to construct surface facilities, a 5,101 ft. deep shaft and associated underground workings to explore the property. Similar geologic conditions which exist at the Galena mine extend into Caladay below the level of the current workings. The facilities are used to benefit the Galena Mine operations by providing additional ventilation.

Mineralization

Ore deposits of the Coeur d’Alene Mining District and USSC are hosted by slightly metamorphosed Precambrian sedimentary rocks of the Belt Supergroup. Belt strata are composed primarily of fine-grained quartz and original clay (now metamorphosed to fine-grained white mica, or sericite). Although the composition of these metasediments varies widely, three major rock types are generally recognized. These rock type definitions were first applied in the district to the Revett Formation (White and Wilson, 1982) but have since been used in describing other Belt formations as well. The rock types are; vitreous quartzite, sericitic quartzite, and siltite-argillite.test

The ore bodies at USSC’s property occur as steeply dipping fissure filling veins. The veins cut through the rocks of the Revett Formation and are found along major fracture systems and major faults. The veins generally strike east west and northeast southwest and range in thickness from a few inches to over fifteen feet. Two different ore bearing sulfide assemblages are found at the Galena, a silver-copper ore and a silver-lead ore. Grades of the silver-copper veins range from a few ounces of silver to over a thousand ounces of silver per ton and since 1953 have averaged over 22 ounces per ton. Copper grades range from tenths of a percent to over two percent and since 1953 have averaged 0.83 percent per ton. Grades of the silver-lead ores average approximately 13 ounces of silver and 16% lead per ton.

The cross-section shows the Revett Fm in the in core of the Big Creek anticline and the position of the productive veins discovered to date on the North limb of the anticline. The beds dip steeply to the north and the faults dip steeply to the south. On a local scale the Revett Fm consists of interbeds of hard (brittle) and soft (ductile) units, the interbed can be from inches thick to over a 100 feet thick.

Exploration Targeting

Historic exploration at the Galena and Coeur mines was carried out by following the “trend” of the veins with drifting and diamond drilling. This method was successful but it is believed that it did not allow for recognition of the larger picture of the geologic interplay of faults, veins, and stratigraphy. One obvious effect of the trend based exploration was that the underground workings at the Galena mine were developed in NW-SE direction from the central shafts. The directional development has caused large prospective areas of the Galena and Coeur mines to remain unexplored. One such area is the hanging wall of the Polaris fault. The single largest and most productive vein in the Galena and Coeur mines is the Galena’s Silver vein which has produced over 25 million ounces of silver and is located in the hanging wall of the Polaris fault. The trend based exploration caused the workings to be developed in northwesterly trend because of numerous secondary ore vein bearing veins in the footwall of the Silver vein. This development direction caused the workings to cross into the footwall of the Polaris leaving the entire hanging wall of the Polaris fault virtually unexplored for about 4 miles from the eastern side of the Galena to the boundary with the Sunshine Mine.

Structural control on vein mineralization has long been recognized in the Coeur d’Alene District. However, using these observations in developing predictive exploration models has proven difficult. With the advent of 3-D modeling software the integration of structure, stratigraphy and geochemistry into a three-dimensional model for use in exploration has been facilitated and is being carried out at Coeur Silver Valley.

The basis of the current structural work at the Galena is that the emplacement of the vein arrays is structurally controlled. There are secondary controls imposed by stratigraphy and geochemistry but structure is considered the most dominant because the movement of fluid required for vein and mineral precipitation requires the presence of active structures. A geometric model of the Coeur-Galena was constructed in Datamine Studio software, which has allowed for examination of the faults and veins and their relationships to one another.

John P. Ryan

CEO: April, 2006 – Present: "US Silver Corporation" (USA.V)

Director: July, 2006 – Present:"Consolidated Goldfields" (CDGF.PK)

CLO (Chief Legal Officer): January, 2006 – September, 2007: "Platinum Diversified Mining" (PDM:AIM)

Director: November, 2006 - Present: "Tomco Energy PLC" (TOM:AIM)

CFO: March, 2006 – Present: "Pangea Pictures Corporation"

Secretary: November 2005 – March, 2006: "Cadence Resources Corporation" which is now "Aurora Oil & Gas Corp". (AOG:AMEX)

VP, CFO: December 2000 October, 2005: "Cadence Resources Corporation" which is now "Aurora Oil & Gas Corp". (AOG:AMEX)

VP, CFO: April 2004 – June 2006: "High Plains Uranium" (HPU.TO) merged into "Energy Metals" (EMU.NYSE Arca), subsequently merged into "Uranium One" (UUU.TO)

CFO: August 2001 – Present: "Trend Mining Company" (TRDM.PK)

VP, CFO: July 2000- February, 2003: "Western Goldfields, Inc." (WGI.TO)

VP of Corporate Development: April, 1995 – August, 1998: "Royal Silver Mines, Inc." restructured as "Cadence Resources" in 2000

Director, VP June, 1996 - April, 1999: "Metalline Mining Company" (MMG:AMEX)

B.S. Mining Engineering (1985) University of Idaho; J.D. (1992) Boston College Law School

ee also

* Hard rock mining

External links

* [http://www.us-silver.com/ US Silver]


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